This disclosure relates to thermoplastic compositions and in particular to low smoke, low heat release, and weatherable thermoplastic polymer compositions comprising polycarbonatesiloxane-arylate, methods of manufacture, and uses thereof.
Polycarbonates are useful in the manufacture of articles used in mass transportation such as trains, aircrafts, and buses. These applications have stringent flammability safety requirements that the polycarbonates must meet. Particular requirements include smoke density, flame spread, and heat release values.
A number of polycarbonate compositions have been able to pass the tests set forth for interior aircraft or train applications. However, these compositions may be susceptible to yellowing after light exposure, which can adversely impact the color stability performance of the compositions. This yellowing phenomenon, sometimes referred to as photoyellowing, has been difficult to address with known techniques and materials, especially for some colors and some shades of some colors. Accordingly, there is a need for materials that can meet the stringent fire safety requirements, yet provide color stability across a variety of targeted color specifications.